Revised research finds air pollution health risks were overstated

| Tuesday, June 11, 2002

Researchers
revising a study of tiny pollution particles from diesel engines
and power plants have uncovered a computer glitch that could
mean less health risk than previously thought. The flawed findings
have some wondering if it means a possible delay in new federal
rules.

Scientists
at Johns Hopkins University determined the software used for
the study of 90 American cities overestimated the increase in
the typical mortality rate. The software in question could be
a problem for the Environmental Protection Agency as it prepares
to issue even stricter clean air regulations by the end of next
year. Many of the more than 100 studies the agency is examining
use the software.

A spokesperson
with the university's biostatistics department said they still
believe strongly in the link between the particulate matter
and the health effects it creates. In fact, the new research
doesn't weaken the largely accepted link between air pollution
and premature death. But it cut by half the previous estimate
about the rate of increase in the death rate compared to increases
in the number of particles in the air.